Justification:
Extent of occurrence of over 101,500 km² and known from more than 20 locations, seemingly common species. Populations in northern and western parts of range likely threatened by human activity, but eastern and southern populations protected by presence in natural parks (including Parques Nacionales Tolhuaca, Lanín, Nahuel Huapi, Los Alerces; Muzón and von Ellenrieder 1999).

Upper end of small forested stream valleys. Carle (1996) indicated that larvae are typically found in streams less than 50 cm wide, under rocks and logs, wet or submerged. Larvae remain undescribed. Carle (1996) also reported that the majority of specimens of this species were collected while flying in a slightly undulating fashion at 0.3-1.5 m along forest paths near the upper end of small forested stream valleys. According to G. Fleck (pers. comm. 2004) the species flies only while the sun is shining; he observed male flight as linear, somewhat undulating vertically, rather fast and unidirectional over small rapid mountain streams, and one female flying rather fast, with some zigzags, 2-2.5 m above the stream, in a circular path returning to the same point after a few seconds. Known flight period extends from November to February (von Ellenrieder 2005).